1. Field of the Invention
This invention relates to knives, and in particular, to a knife that is easy to deploy.
2. Description of the Related Art
Knives have long been used to perform a variety of tasks, and knife designs have been adapted accordingly. While some knives are designed for extremely specialized applications, many people carry knives for general purpose use, and there is a significant demand for knives that are useful for a broad range of applications. Two categories of knives are fixed blade knives, and pocket knives. Fixed blade knives generally comprise a handle and a blade rigidly fixed together and configured to be received into a sheath or scabbard that may be attached to the user's belt. Fixed blade knives provide many advantages, including ease of access and robust construction. The handle and blade of a fixed blade knife that is carried on a belt is generally around eight inches long, or longer. A knife of this size hanging from one's belt tends to interfere with normal movement, such as entering and exiting vehicles, sitting and bending, etc. Additionally, a knife of this size can attract the attention and concern of those around the user.
A pocket knife generally includes a handle and a blade coupled to each other in such a way that the blade can be stored within a cavity inside the handle. Most common of these are folding knives, in which the blade is pivotally mounted at one end of the handle such that it can be rotated around the pivot and folded into the cavity in the handle. In other cases, the blade may be slideably mounted to the handle such that the blade is translatable between a retracted position in which the blade resides in the cavity inside the handle, and an extended position in which the blade extends from an opening at one end of the handle for use. Such knives are often referred to as out-the-front (OTF) knives. While folding and OTF knives are referred to here as pocket knives, in many cases such knives are provided with other means for carrying. For example, belt sheaths are often used with such knives, especially in the case of larger knives. The belt sheath allows a user to carry the knife without having its weight and bulk within a trouser pocket. Even though when deployed such a knife may be as long or longer than belt knife described above, it occupies a much smaller area while stored and thus presents fewer problems for the user, both as a practical matter and in appearance. Another common adaptation for carrying a pocket knife is the use of a pocket clip: generally, a spring clip that extends down one side of the knife handle and is used to clip the knife into the user's pocket or on the user's belt.
While pocket knives do not suffer from the disadvantages inherent with belt knives, they do have disadvantages of their own. For example, preparing to use a pocket knife is generally more complicated than deploying a belt knife, since it includes removing the knife from the pocket or sheath, and then unfolding or extending the blade to a position for use. The act of deploying a blade often requires that the user insert a thumbnail into a notch formed along the back edge of the blade in order to pull the blade out of the handle, or may require that the user press against a stud to rotate the blade out of the handle. In many cases, two hands are required to deploy a blade in a pocket knife. An early solution to this problem was the creation of automatic knives, or switchblades, in which a spring-loaded mechanism is provided such that, when a user presses a release button on the handle of the knife, the spring moves the blade from the stored position to the extended position. With such a mechanism, it is possible to easily deploy the blade of a knife with one hand, thereby resolving many of the difficulties associated with pocket knives. At one time, automatic knives were very popular. However, laws passed in the 1950's generally made automatic knives illegal for carrying.
Recently, other knife designs have emerged for knives that can be opened with one hand in order to provide users with greater convenience and practicality. However, even in these newer designs, a certain degree of dexterity is required in order to open the blades, and there are many applications where a more easily deployable knife would be very useful. For example, if a user is in an environment where gloves are required, it may be still be difficult to manipulate thumb studs or move release levers in order to open a knife. Thus, there remains a demand for improved knife designs, particularly in the area of one-handed knives.